Door closer



May 24, 1960 w. c. FREwER 2,937,397

DOOR CLOSER Filed March 28, 1958 2 Sheets-Sheet 1 Maly 24, 1960 Filed March 28, 1958 W. C. FREWER DOOR CLOSER 2 Sheets-Sheet 2 DOOR CLOSER William Charles Frewer, Poole, England, assignor to Thomas Joseph Doran, Hove, England Filed Mar. 28, 1958, Ser. No. 724,748

2 Claims. (Cl. 16--51) The present invention relates to door closers and has as an object to provide a closer which is neater and simpler in ope-ration than the known door closers.

Heretofore door closers have comprised a main housing which is secured to the top of a door and connected to the door frame by means of a knuckle joint. The housing contains the main operating spring which gives the loadlng for closing the door, and also the dash pot damplng device to give a regulating speed of closing. Because of the size of the housing necessary for containing this mechanism the closer has had to be secured to one face of the door with the operating amis secured to an exposed part of the door frame. This is frequently undesirable since -it is regarded as unsightly.

A further object of the invention is to provide a door closer which when the door is closed is wholly concealed from view,

According to the present invention a door closer cornpr-ises an arm adapted to be pivoted at one end to the door frame or to the door for horizontal swinging movement and spring loaded to be urged to rotate in one direction, and a dash pot device adapted to be secured to the door or door frame and having a member connected to the =free end of the spring loaded arm for opposing the said rotation of the arm, the said member being adapted to reciprocate in a substantially straight line.

It will be apparent that if the spring loaded arm is secured to the door trame then the dash pot device is secured to the door and vice versa.

Conveniently the spring loaded arm is spring loaded by means of a coiled compression spring surrounding its vertical pivot and housed in a cylindrical housing which can be adapted to be received in a recess in the door frame and thus be concealed from View.

The dash pot device may comprise a piston operating in a cylinder which is closed at one end and provided at its rear end with a suitable oil seal through which passes the piston rod the rear end of which projects beyond the oil seal and carries a block running in a slot adjacent the rear end of the cylinder and having a stem projecting through said slot which stem acts as the pivot for the free end of the spring loaded connecting arm. Suitable means may be provided for controlling 'the passage of oil from one side of the .piston to the other both when the door is being opened and for controlling the reverse flow of oil during the closing action of the spring.

To allow dior free passage of oil from one side to the other whilst the door lis opening a one way ball valve may be provided in the piston.

To control the return of the oil to the other side off the piston during closing of the door the oil may be caused to pass through a centre boring in the piston rod which extends to the front or operative face of the piston and through a port extending laterally from the centre boring to the periphery of the piston rod behind the piston. This laterally extending port can be controlled by means of a needle valve one end of which extends to the rear end of the piston rod and is controlled by a States Patent F 2,937,397 v Y Patented May *24, 1960 ice 2 nut or knurled head to regulate the ow of oil to the rear of the piston( In order that the closer means may have suicient pressure to operate the door latch, means may be provided to decrease the damping elect of the oil over the last portion of the travel of the door to the closed position. This may be achieved by providing a secondary passage for the oil past the piston over the last portion of its travel whereby the damping elect of the dash pot on the spring pressure is partially or wholly relieved.

Conveniently means may be provided for Vcutting out the secondary passage when snap closing is not desired.

The invention will now be described withreference to the accompanying drawings illustrating a specilic embodiment suitable for recessing into the door `frame and the doo-r so as to be hidden ffrom view.

In the drawings: Y v

Figure 1 is a longitudinal sectional View of a doo closer according to the invention, and

Figure 2 is a plan view, partly broken away and partly in section of the construction of Figure l.

In the drawings there is shown at 1 the upper edge portion of a door and at 2 a portion of the top frame member of the door frame. The door closer comprises a dash pot assembly indicated generally at 3, a return spring assembly indicated generally at 4, and a pivoted arm 5 connecting the dash pot to the return spring.

The dash pot assembly 3 comprises an elongated mounting plate 6 adapted to be received in a recess 7 in the upper-edge surface of the door, a cylinder 3 secured to the under surface of the mounting plate, a piston 9 operat-l ing in thecylinder 8 and having a tubular piston rod 10 which extends rearwardly from the cylinder to support a pivot block 11 to which one endof the arm 5 is pivoted.

The cylinder 8 is conveniently made from a length of standard gauge tubing secu-red at each end in cylinder blocks 12 and 13 respectively secured to the plate 6 by screws 14' and located by means of 'dowel pins 15. The cylinder end block 12 is closed by means of a sealing plug 16 threaded therein vand the end block 13 is apertured to accommodate a seal 17 through which the piston rod 10 Vcan slide. The cylinder 8 extends for about half the length of the mounting plate 6 and the upper edge surface of the door is further recessed as at 18 to accommodate the cylinder 8 and to permit movement of the pivot block 11 longitudinally of the mounting plate v6.

As will be seen from Figure 2, the mounting plate 6 is of a width less than the thicknessfof the door, and the recesses 7 and 18 open into one face of the door. Thus if the said one face of the door is the inner face thereof i.e. the face that abuts Tthe door frame when the door is closed, the mounting plate 6, cylinder 8 and pivoted arm 5 will be invisible from the outer face of the door.

The mounting plate 6 is provided with a longitudinally extending slot 19 through which the upper portion of the pivot block extends and is slidably guided thereby.

The return spring assembly 4 comprises a cylindrical'r housing 20 secured to :a plate 21 by means of screws 38 which pass through apertures in the outwardly turned ange 39 to engage a threaded member 40 which surrounds the lower end of the housing. The housing 20 is adapted to be accommodated in an upwardly extending recess in thedoor frame member 2 and to be secured therein by screws (not shown) extending upwardly through extensions of the plate 2l into the member Z. The plate 21 supports an end member 22 of the housing 20 which end member rotatably supports a stub shaft 23 extending therethrough and having a splined portion 2.4 positioned below the plate 21 and adapted to engage in a suitably shaped aperture 25 in the arm 5 so that the arm is rigidly secured to the stub shaft 23 for rotation therewith. A torsion spring 26 is accommodated in the housing 20 and is anchored at its upper end thereto as at 27, the lower end of the spring being secured in a bracket 28 secured to the stub shaft 23.

The arm is thus spring loaded by the spring 26 so that when the arm is rotated in an anti-clockwise directi'on (as viewed in Figure 2) upon opening of the door, the spring 26 is tensioned and when the door is released, the spring causes the arm to swing back in a clockwise direction to effect closing of the door. ,It will be appreciated that since the housing 20 is accommodated in a recess in the door frame member 2, it is effectively concealed when viewed from either side of the door.

As will be clearly seen in Figure 1, the tubular piston rod extends through the piston 9 so that the bore of the rod opens on to the front face of the piston. Behind the rear face of the piston there is provided a laterally extending port 29 communicating the bore of the pistou rod with the interior ofthe cylinder 8. The ow of oil through the port 29 is controlled by means of a valve member in the form of a rod 30 extending through the piston rod and having at its front end a dat 31 which, with the interior periphery of the bore of the piston rod, provides a channel leading to the port 29. By rotating the rod 30 with respect to the piston rod, the port 29 can be partially covered by the unattened part of the periphery of the rod 30 thereby providing an adjust able restriction means for restricting the iiow of oil from the front of the piston, through the channel formed by the at 31 and the uncovered portion of the port 29, to the interior of the cylinder behind the piston. In order to elfect the said adjustment of the restriction means, the rod 30 extends rearwardly from the pivot block 11 to receive an adjusting handle 32 which is rotatable between a pair of fixed stops 33 defining the fully open position and the position of maximum restriction respec tively.

To permit the flow of oil from the rear of the piston to the front thereof when thepiston is moved rearwardly upon opening of the door, a pair of channels 34 (Figure 2) extend through the piston, each being provided with a ball valve 35 for preventing the ow of oil therethrough when the piston is moved forwardly upon closing of the door.

` In operation of the door closer described, when the door 1 is swung in the opening direction i.e., in the direction of the arrow 36 in Figure 2, the arm 5 pivots in an anti-clockwise direction (as viewed in Figure 2) about its fixed pivot provided by the stub shaft 23 and thereby draws the piston rod rearwardly, the oil in the cylinder 8 passing freely through the channels 34 to the front of the piston. At the same time, the pivoting of the arm S rotates the stub'shaft 23 and tensions the spring 26.

f When the door is free to return to the closed position, the arm 5 under the action of the spring 26 rotates in the clockwise direction as viewed in Figure 2 thereby causing the door to swing towards the closed position. At the same time the arm causes the piston to move forwardly which forward movement is opposed by the oil in front of the piston which passes from the front to the back of the piston at a controlled rate determined by the extent of the opening of the port 29, and thereby controls the speed at which the door closes under the action of the spring 26.

If it is desired to provide a snap closing of the door in order to overcome the resistance of the door latch at the end of the door closing movement, a means may be provided for relieving the oil pressure on the front of the piston during the last portion of the forward movement of the piston, so that over this last portion, the force of the spring 26 is practically wholly effective on the door.

One method of providing such snap closing in the door closer described is to provide a longitudinally extending groove or channel in the inner periphery of the cylinder 8 at the front end thereof as indicated in broken lines at 37 inFigure l. Thus when the piston 9 is approaching its extreme forward position and depending on the length of the groove 37, oil is free to ow through the groove from the front to the rear of the piston thereby relieving the oil pressure opposing the force of the spring 26 and annulling to a substantial extent the control of the dash pot assembly on the closing action of the spring 26.

I claim:

l. A door closer comprising an arm, means for mount ing said arm at its ends on a door and on a door frame respectively, the said mounting means comprising a pivotal support at one end of the arm for supporting the arm for horizontal swinging movement in one direction upon opening of the door and in the other direction upon closing of the door, spring means biasing said arm to swing in the said other direction to close the door, and a dash-pot device connected to the other end of the arm for opposing swinging movement of the arm in the doorclosing direction, the said dash-pot device comprising a cylinder supported on an elongated mounting plate extending axially thereof, a longitudinal slot in said mounting plate, a piston slidable in said cylinder, a piston rod secured at one end to the piston and supporting at its other end a pivot block slidably engaging in said longitudinal slot and pivotally supporting said other end of the arm thereby to constrain said other end of the arm to move along a straight path.

2. A door closer as claimed in claim 1 in which the said dash-pot device includes means providing a passage for the free ow of uid from one side of the piston to the other side thereof when the piston is moved in one direction by swinging of the arm in the door-opening direction, means for restricting the ow of uid from said other side to said one side of the piston when the piston is moved in the other direction by swinging of the arm in the door-closing direction, and means permitting substantially unrestricted flow of uid from said other side to said one side of the piston when the piston approaches the end of its movement in said other direc tion, thereby to provide final snap closing of the door to overcome the resistance of the door latch.

References Cited in the file of this patent UNITED STATES PATENTS 

